Dosage Compensation in Mammals Typically Involves the Random Inactivation of One

Dosage compensation in mammals typically involves the random inactivation of one of the two X chromosomes relatively early in development.Such X chromosome inactivation often leads to phenotypic mosaicism.Assume that black fur in cats is due to the X-linked recessive gene b,whereas its dominant allele B produces yellow fur.A Bb heterozygote is a mosaic called "tortoise shell" or "calico." Using appropriate gene symbols,diagram a mating between a black male and a calico female.Give the phenotypes and genotypes of all the offspring.